I think any time I mistakenly use SRS expecting that it represents the learning process rather than it facilitates learning, I'm prone to this syndrome. More explicitly, the learning process involves active use and problem solving, creating a web of connections between concepts. SRS merely changes conceptual recall times. For a CS analogy, it moves the memorized concept to main memory instead of residing on a slow disk or over the network. Cumulative slow seeks frustrates learning, so this is useful. But, having something in fast memory isn't useful if you don't have an index to it -- the absence of which (contextually) is flashcard blindness.
I've also felt this problem a lot too, but haven't found a good alternative for self study. Anki/flash card needs to be a support, that uses the minority of your study time, and links closely to the other parts. This is easier when following a class, than when doing self-study.
It is so easy to build elaborate flashcard strategies and get lost in implementing them.
Flash card-based methods are very fast, especially in the beginning. Reading goes further, but is too slow for the first maybe 1000-2000 words (depending on the language).
If this technique did help at all I think the effect was mainly psychological. Looking at a page with a bunch of words you don't know is stressful and demoralizing. Even being able to think that you have seen a character somewhere without knowing what it means can be comforting. It sounds silly but any amount of stress can severely inhibit language acquisition. You might be better off meditating for 15 minutes... Or taking drugs
The only thing that seemed to be 100% effective was readimg content that I was completely engaged in. It didn't matter if said content was close to my skill level or way beyond my skill level. As long as I am sufficiently engaged it doesn't matter how many times I have to reference the dictionary or comb google for grammar explanations.